Sources of Infectious & Non-Infectious Contamination during LASIK Surgery

Sources of Infectious & Non-Infectious Contamination during LASIK Surgery

One of the ultimate goals in performing any surgical procedure is to minimize less-than desirable outcomes arising from both infectious and noninfectious contaminants entering the surgical field. This is especially true of all corneal procedures, such as LASIK, where the normal mechanisms for fighting contaminations are diminished. As with any surgical procedure, a potential complication of LASIK is postoperative infection.

How would my eye get contaminated?

The surgical field boundaries of the standard LASIK procedure include the patient's lid margins, lashes, cul de sac tissues and surgical drape if used. These regions can be sources of contamination. As for the pathogenic contaminants, although any microbial agent may create an infection, the majority of post-LASIK infections are caused by atypical pathogens such as nontuberculous mycobacteria and Nocardia species. Infection caused by these organisms can occur at any time in the postoperative course.

What are the main types of cornea infection?

Corneal infections can be caused by bacteria, fungi, parasites or viruses and, accordingly, can be classified as bacterial, fungal, viral and parasitic eye infections. Common factors that aggravate or facilitate such infections include severe dry eyes, an abrasion, a foreign object in the eye, severe allergies and an inflammatory disorder. However, fortunately prevention and / or treatment of such infections are possible with the help of sterilization, application of antiseptics & proper antibiotics during and after the LASIK surgery.

How do the contaminants get in?

During the LASIK procedure, direct contact with lid margins, lashes, surgical drapes and invasive solids and fluids can arise owing to the involuntary introduction and inclusion of infectious organisms, epithelial cells, debris, oils and tear duct secretions into the stroma after the corneal flap is reflected back off the corneal surface. Manipulations of both epithelial and stromal surfaces of flap and bed, introduction and extraneous use of instruments to the interface, flap folding, coupled with inefficient plume evacuation, non-uniform and varying hydration of the target stroma, stromal bleeding, prolonged flap adherence time, involuntary saccadic and cyclorotational ocular movements throughout the LASIK procedure may each contribute to less than desirable outcomes. Moreover, lack of, or inefficient, removal of plume can lead to deposition of smoke particles on the laser's exposed optics, increasing the need for cleaning or replacement. It has been widely observed by surgeons that sometimes the generated plume carries large particles, which could drop out onto the surgical field creating additional contamination in the region of the incision and/or these particles adhere after splattering onto the laser's last optic resulting in irregular etching. Both events cause grief for the surgeon and patient and may require complex surgical intervention in an attempt to correct poor outcomes. Additionally, splatter; smoke and large particles are possible health and safety issues for the surgeon, medical staff and patient.

Is there any way to make sure it doesn’t happen?

Due to the preponderance of atypical organisms in the setting of post-LASIK infection, the clinician confronted with postoperative in?ammation must maintain a high index of suspicion. This may involve limiting health care worker (surgeon and nurse) contact with all secretions or biological fluids, skin lesions, mucous membranes, and blood or body fluids. Health care workers must wear gloves for each contact which may lead to contamination, and gowns, mask and eye protection where contamination of clothes or the face is anticipated. However, the first and the foremost line of defense for preventing eye infection, in addition to careful aseptic technique, is the aggressive prophylactic treatment / application by antibiotics. Some of these antibiotics include fluoroquinolones such as ciprofloxacin, levofloxacin, and ofloxacin.

  • On the other hand, the patient must keep his / her eyes closed as much as possible in the 24 to 48 hours after surgery. This allows the surgical site time to heal and prevents debris from entering the area.
  • Do not rub the eye that was operated on. If a flap was made during surgery, rubbing your eyes can cause the flap to move, delay recovery and possibly cause infections or complications.
  • Similarly, you must always wash your hands before applying eye drops to prevent contamination.
  • Even after surgery, you should protect the eyes after surgery to prevent injury.
  • Use eye drops and any medicine as prescribed by your doctor. Stick to the schedule for prescribed eye drops and medications to allow the eyes to heal in a timely fashion. Keep moisture drops in your pocket or purse to prevent dryness and discomfort.
  • Wear protective eye covering. While sleeping, using eye shields for one week following surgery can prevent damage from nighttime movements. Showering with eye shields helps avoid the temptation to rub your eyes and can aid in stopping contamination from shampoo and soaps. Eye shields can include goggles, eye masks and eye patches with tape.

Are there any risks associated with treatment?

The pharmacologic treatment of post-LASIK infection is with empiric, broad-spectrum, forti?ed antibiotics (cefazolin 50 mg/ml and tobramycin 15 mg/ml, each used hourly) until the causative organism can be identified. In the case of infections due to atypical organisms, which historically are quite difficult to eradicate, long-term treatment for several months, with less commonly used topical antibiotics such as amikacin, clarithromycin and azithromycin, may be required.

Is there anything that can be done to make the open area less susceptible to contamination?

A mandatory practice in all hospitals and surgical rooms is keeping everything sterilized and clean throughout the day, every day. All bed linens, paper patient garments and trash should be removed from the room. It should be disposed of properly according to hospital guidelines. All flat surfaces must be wiped down with a sterile pad and antimicrobial solution. 

What if dust falls in my eye during the LASIK surgery?

If, for any reason, some dust or debris falls in your eye(s) during the LASIK surgery, it may lead to the formation of the so called corneal abrasion. A corneal abrasion is an injury to the front surface of the eye. The injury can occur when a foreign object gets in the eye, when the cornea becomes scratched, or even from rubbing the eyes too hard. Small abrasions can heal within 24 hours but more severe abrasions can take up to several weeks to heal. This injury can be treated in different ways. The doctor will probably prescribe eye drops and/or ointment. You may need to wear a special contact lens overnight or longer to help with healing. Sometimes a patch may need to be worn on the eye overnight. In some other cases, dust or debris can also lead to other eye problems such as corneal infection and dry eye.

Related Articles:

Learn more about sources of contamination during LASIK eye surgery on our forums!